Runner’s World Energy Gels: A Step-by-Step Guide for Marathon Runners (2026)

By Ethan Brooks

Updated November 2026

Runner’s World energy gels are one of the most common fuels in endurance running, and they work well when you use them on purpose. This guide walks you through choosing a gel, timing it, practicing with it in training, and avoiding the mistakes that cause stomach trouble on race day. By the end, you will have a simple, tested fueling routine for runs longer than about 75 minutes.

What Runner’s World Energy Gels Are and Why Runners Use Them

Energy gels are concentrated carbohydrate products, usually 20 to 30 grams of carbohydrate per packet, designed to be swallowed quickly without chewing. Most are built around maltodextrin, sometimes combined with fructose, and many include sodium and potassium. The format matters because your body can only absorb so much carbohydrate per hour, and gels deliver it in a small, portable dose.

Shopping for one? See our guide: GU Roctane Energy Gels Review: Pros, Cons and Who It's For.

Runner’s World has covered gels extensively in its training and nutrition coverage, and the general advice in that coverage matches what sports nutrition guidance says: gels are a practical way to replace the glycogen you burn during prolonged effort. They are not a replacement for regular meals. Think of them as a tool for the run itself, not for your overall diet.

Step 1: Decide Whether You Need Gels at All

Not every run calls for fuel. Your body stores enough glycogen for roughly 60 to 90 minutes of moderate effort if you have eaten well the day before. For shorter runs, water and a normal pre-run meal are usually enough.

A rough guide:

• Under 60 minutes at easy pace: usually no gel needed.
• 60 to 90 minutes, including tempo or race-pace work: a gel may help, especially if you start the run with a lighter breakfast.
• Over 90 minutes: plan on gels, starting around the 45- to 60-minute mark.
• Marathon and long half-marathon efforts: gels are a core part of the race plan.

If you have a medical condition, are pregnant, or take medication that affects blood sugar, check with your doctor or a registered dietitian before changing your fueling routine.

Step 2: Choose a Gel Based on Your Stomach and Goals

Gels differ in carbohydrate content, caffeine, sodium, flavor, and texture. The best gel is the one your stomach tolerates at race effort, not the one with the most impressive label. For a broader look at how options compare, see Top 6 Energy Gels for Runners Compared in 2026.

Key factors to compare

• Carbohydrate per packet: Most gels provide 20 to 25 grams. Some high-calorie formulas go higher, which can mean fewer packets but a heavier stomach load.
• Carbohydrate type: Gels with a maltodextrin and fructose blend are common for longer efforts because they use more than one absorption pathway.
• Sodium: Useful in hot weather or for heavy sweaters. Check whether it fits your sweat losses.
• Caffeine: Helpful late in a race for some runners, but it can disrupt sleep and cause jitters. Test it in training.
• Texture and water needs: Thicker gels generally require more water to swallow comfortably.

If you follow a specific diet, the related guides on Gluten Free Energy Gels: 6 Best Picks for Marathon Runners (2026) and Top 5 Best Low Carb Energy Gels Compared for Keto Runners cover those niches in more detail.

Step 3: Time Your First Gel Correctly

Timing is where many runners go wrong. Taking a gel too early can cause unnecessary stomach load, while waiting too long means your glycogen is already low. For most runners, the first gel should go down between 40 and 60 minutes into a run. If you are running a marathon, many coaches suggest starting around 45 minutes and continuing at regular intervals from there.

For a deeper breakdown of timing strategies, read When to Take Energy Gels: A Marathoner's Timing Guide.

Step 4: Set Your Intake Schedule

A common target is 30 to 60 grams of carbohydrate per hour during prolonged running, and well-trained runners sometimes go higher, up to around 90 grams per hour using multiple carbohydrate types. Divide that target by the carbohydrate content on your gel to find your interval.

1. Find the carbohydrate per packet on the label. Suppose it is 25 grams.
2. Choose an hourly target. Say 50 grams per hour.
3. Calculate packets per hour: 50 divided by 25 equals 2 packets.
4. Space them evenly: one packet about every 30 minutes.
5. Write the schedule on your hand or pace band so you do not have to think on course.

Start with the lower end of the range during training, then increase gradually. Most stomach problems come from jumping straight to a high intake without practice.

Step 5: Practice in Training, Not on Race Day

Race day is the wrong place to discover that a gel does not agree with you. Use your long runs to test each gel at the exact intervals and with the water you plan to use. Record what you took, when, and how you felt for the next hour.

Sub-steps for practice

• Test at least two or three long runs with your planned strategy.
• Use the same gel brand and flavor you will race with, since flavors can vary in texture.
• Run at race pace for part of the practice run, because stomach tolerance drops under higher effort.
• Try a sip of water with each gel to see how it feels, and adjust.

Step 6: Use Water and Sodium Wisely

Gels are thick. Swallowing one dry can be unpleasant and sometimes triggers gagging. Take a few sips of water with each packet, but avoid drinking large volumes that slosh around your stomach. Aid stations are usually spaced to give you water, and many races also offer sports drinks. Know which one your race provides and whether it matches the sodium in your gel. If you are using a gel with sodium on top of a high-sodium sports drink, you may be getting more than you need.

Common Mistakes With Energy Gels

• Trying a new gel on race day. Always test first.
• Taking gels too late. Waiting until you feel empty means you are already behind.
• Skipping water. Dry swallowing leads to gagging and nausea.
• Doubling up at aid stations. Taking a gel plus a sports drink plus a banana in one stretch can overload your gut.
• Ignoring the label. Caffeine, sugar alcohols, and sodium levels vary widely between products.
• Using gels as your only fuel. Eat real meals and snacks on the days before and after long runs.

Recommended gear

A few practical items make gels easier to carry and use on the run.

• Running belt with gel loops: Keeps packets secure and reachable without stopping. View on Amazon
• Soft flask or handheld water bottle: Lets you take sips with your gel without carrying a heavy bottle. View on Amazon
• Pace band or waterproof gel schedule card: Keeps your intake timing visible during a race. View on Amazon

FAQ

How many energy gels should I take in a marathon?

Many runners take three to five gels over a marathon, depending on the carbohydrate content and their pace. Your exact number should come from training practice. For detailed planning, see How Many Energy Gels for Half Marathon Runners Need: A Step-by-Step Plan.

Can I take a gel before I start running?

Some runners take a gel about 10 to 15 minutes before the start, but it is not required. Pre-race meals earlier in the morning usually do more for your fuel stores. Test any pre-start gel in training first.

Do energy gels expire?

Yes. Check the best-by date on the packet. Heat can also degrade texture and flavor, so store gels in a cool place and avoid leaving them in a hot car. For storage and shelf life questions, see How Long Do Energy Gels Last in Your System? A Runner's Guide.

Why do energy gels upset my stomach?

Common causes include taking them too early or too often, not drinking enough water, running at high intensity, or a gel with ingredients your gut does not tolerate well. Reducing volume and practicing more often usually helps.

Are energy gels bad for my teeth?

Frequent sugar exposure can contribute to tooth decay. Rinsing your mouth with water after a gel and waiting before brushing can help. For more detail, see Are Energy Gels Bad for Your Teeth? What Runners Need to Know.

Can I use gels if I have diabetes?

Possibly, but you need a plan. Blood sugar responses vary, and the timing and dosing should be discussed with your healthcare provider. The guide on Energy Gels and Diabetes: A Step-by-Step Guide for Runners (2026) is a starting point, not a substitute for medical advice.

Should I choose caffeinated or caffeine-free gels?

It depends on your tolerance and goals. Caffeine can help some runners late in a race, but it can cause jitters, sleep problems, or stomach upset. Only use caffeine you have tested in training. Runners who avoid it entirely can find options in 6 Best Caffeine Free Energy Gels for Runners in 2026.

Do I need to take gels on every long run?

No. Practicing your race fueling on some long runs is useful, but you do not need gels on every run. Many runners use them mainly on longer sessions and races.

Conclusion

Runner’s World energy gels can carry you through long runs and races when you choose them carefully, time them well, and practice before race day. Start with a gel you can tolerate, take the first packet around 45 minutes in, and keep to a steady hourly schedule. Refine the plan on your long runs, and your race-day fueling will feel routine instead of experimental. If you have health concerns, check with a qualified professional before changing your fueling.

About Ethan Brooks

Ethan Brooks is part of our editorial team and reviews and edits our marathon & half-marathon guides, checking product details against manufacturer specifications and owner feedback.